Volt Documentation

Generates an HMAC (Hash-based Message Authentication Code).

Syntax

crypt.hmac(data: string, key: string, algorithm: string?) -> string

Parameters

Parameter	Type	Description
`data`	`string`	The data to authenticate
`key`	`string`	The secret key
`algorithm`	`string`	(Optional) Hash algorithm, default "SHA256"

Returns

Type	Description
`string`	The HMAC as a hex string

Description

crypt.hmac generates a keyed-hash message authentication code, which provides both data integrity and authentication.

Supported Algorithms

MD5
SHA1
SHA256 (default)
SHA384
SHA512

Example

local data = "Important message"
local key = "secret_key"

local mac = crypt.hmac(data, key, "SHA256")
print("HMAC:", mac)

Verification Example

local function verifyMessage(data, key, expectedHmac)
    local computed = crypt.hmac(data, key)
    return computed == expectedHmac
end

local key = "my_secret"
local message = "Hello"
local signature = crypt.hmac(message, key)

-- Later, verify the message
if verifyMessage(message, key, signature) then
    print("Message is authentic!")
end

crypt.hash - Simple hashing

crypt.hmac

On this page